Material handling apparatus

ABSTRACT

An apparatus including a conveyor, a receiver below the conveyor, and a gate comprising at least one gate section normally preventing discharge from the conveyor to the receiver and driven longitudinally along the conveyor to permit such discharge.

United States Patent 13,570,666

[72] Inventor Henri A. Delcellier References Cited Hudson, Quebec, Canada UNITED STATES PATENTS [21] APPLNQ 765,372 2,341,014 2/1944 Blair 221 10 22 Filed 001.7,1968 2,541,262 3/1951 Hatcher.... 198/173 [451 Mar-19,1971 2,571,576 10/1951 Hopkins 221/10 [731 AS81811 f ll'gem'l-Rand v 3,346,092 10/1967 Bowden 198/205 Llmited 3,404,775 10/1968 McClellan 19 8/66 Montreal, Quebec, Canada MATERIAL HANDLING APPARATUS Primary Examiner-Richard E. Aegerter Attorneys-Carl R. Horten, David W. Tibbott and Robert R.

Paquin 10 Claims, Drawing Figs.

209/82, 209/88, 209/111.7, 198/65 ABSTRACT: An apparatus including a conveyor, a receiver Int. Cl B0ld 23/24 below the conveyor, and a gate comprising at least one gate Field of Search 198/189, section normally preventing discharge from the conveyor to 46, 43, 66, 40, 173; 198/65; 209/82, 88, 74, 111.7; the receiver and driven longitudinally along the conveyor to 221/ permit such discharge.

I32 Z L is 12 IA aoq zz ll 1 I I r 40 2O l 4!; 44 444 5 l1 32 3s 42 6 8 42 L32 319 PATENTED HARISIQTI I 'snw 1 0F 3 INVENTOR HENRI A. DELCELL/ER wad/ ATTORNEY SHEET 2 OF 3 f L INVENTOR 52 5O 48 HENRI A. DELCELL/ER FIG. 4

ATTORNEY this purpose. However, these conventional arrangements,

although usually of obvious utility, are believed to generally unduly hinder the discharge of the material. More specifically, these convendonal arrangements generally are subject to either the disadvantage that the gate is undesirably slow in opening to adegree sufficient to permit passage of material into the receiver, and/or the disadvantage that the construction of the conveyor inherently impedes the discharge.

An object of the present invention is to provide a new and improved apparatus of the type set forth which is particularly constructed and arranged to facilitate the discharge of material from a conveyor to a receiver.

Another object of the invention is to provide a new and improved apparatus of the type set forth wherein the gate is particularly constructed and arranged to facilitate such discharge.

Another object is to provide a new and improved apparatus of the type set forth which, although particularly suited for handling logs, is readily employable to handle other forms of material.

In general, this new and improved apparatus comprises a conveyor longitudinally driven to transport material along a predetermined path, a receiver arranged to receive material from the conveyor, a gate comprising at least one gate element normally preventing discharge of material from the conveyor to the receiver and movable longitudinally along the conveyor to permit such discharge, and motor means for moving the gate element. Moreover, the conveyor preferably is constructed to include a pair of endless webs interconnected by angled driving elements which are arranged to be the sole driving contact between the conveyor and material transported thereby.

Referring to the drawings:

FIG. 1 is a fragmentary elevational view of a material handling apparatus constructed in accordance with one embodiment of the invention;

FIG. 2 is a fragmentary top or plan view of the apparatus shown in H6. ll;

FIG. 3 is an elevational sectional view taken on line 33 of H6. 2, looking in the direction of the arrows;

FIG. 4 is a schematic view of the control system of the material handling apparatus illustrated in FIGS. 1 through 3;

H6. 5 is a fragmentary elevational view of a material handling apparatus constructed in accordance with another embodiment of the invention; and

FIG. 6 is a fragmentary top or plan view of the apparatus shown in FIG. 5.

Referring more particularly to the drawings wherein similar reference characters designate corresponding parts throughout the several views, FIG. 1 fragmentarily illustrates a material handling apparatus designated generally as l0 which is particularly adapted for handling logs 12. The apparatus 10 comprises an endless conveyor 14 suitably arranged to transversely receive legs 12 from a source thereof located to the left-hand side of HO. 1, and longitudinally driven by a conventional drive motor (not shown) in the direction indicated by the arrow A at the left-hand side of FIG. 1. The conveyor 14 is particularly constructed to include a pair of laterally spaced, endless webs, belts or chains 16 which extend around conventional drive and guide rollers or sprockets (not shown) and are interconnected at intervals by transversely extending,

ment of the conveyor M. The conveyor 14 extends along the upper surface of a support or floor 220 having an opening 22; and the belts 16 are spaced apart a distance greater than the length of the logs 12, whereby the driving elements 1% drive the logs 12 across the support 20 and form the sole driving contact between the conveyor M and the logs 12.

A receiver 24 is positioned below the conveyor 14 and directly below the opening 22 in the support 20. The receiver 24 is constructed with an open upper end arranged to receive logs 12 from the conveyor 14 through the opening 22, and extends below the floor or ground level 26. The receiver 24 may be, for example, an extension of the magazine of a pulp grinder or, as will be understood, may be employed for collecting logs 12 for any other desired'purpose.

A gate designated generally as 28 is positioned below the support 20 for controlling the discharge of logs 12 from the conveyor 14 to the receiver 24. The gate 28 is particularly constructed to include a pair or set of gate sections or elements 30 which are constructed of greater width than the length of the logs l2 and normally maintained in closed posi tions below the opening 22 wherein, as illustrated in FIG. 1, they cooperate to prevent the discharge of logs 12 from the conveyor 14 to the receiver 24. The gate elements 30 are slidably mounted for movement longitudinally along the conveyor l4 and, during the operation of the apparatus 10, are driven one from the other longitudinally along the conveyor 14 to open positions wherein they are spaced apart to permit the discharge of logs 12 to the receiver 24. This arrangement of the gate elements 30 to open by movement longitudinally to the conveyor 14 causes the log fall space provided therebetween by their opening to longitudinally extend parallel to the logs 12 on the conveyor 14. Thus, the gate elements 30 rapidly open to positions wherein the log fall space is sufficiently large to permit the passage of a log 12 therethrough; and the logs 12 are prevented from hanging-up atone or both ends on the gate elements 30 as would occur were the latter to open in a direction normal to the conveyor 14.

The gate elements 30 are driven longitudinally along the conveyor 14 between their closed and open positions by individual, double-acting, cylinder-and-piston arrangements each designated generally as 32. The cylinder-and-piston arrangements 32 both are pneumatically powered by pressurized air supplied by a pneumatic supply hose 34 through a pneumatic control system which is indicated schematically as 36 in FIG. l and illustrated in more detail in FIG. 4. The pneumatic control system 36 is connected to each of the cylinderand-piston arrangements 32. by airhoses 52,232 and constructed to cause the arrangements 32 to drive the gate elements 30 in unison to their open and closed positions. The cylinder-andpiston arrangements 32, as illustrated in FIG. 1, each include a cylinder 38 and a piston having a pistonhead 40 in the cylinder 38 and a piston rod 42 projecting axially therefrom. The piston rods 42 are each connected by a pin 44 to a flange 46, affixed to the underside of a respective one of the gate elements 30, such that retraction of the pistons into the cylinders 3% draws the gate elements 30 longitudinally along the conveyor 14 to open positions and, conversely, extension of the pistons moves the gate elements 3% longitudinally along the conveyor 14 to their illustrated closed positions.

The pneumatic control system 36 is solenoid operated to cause the cylinder-and-piston arrangements 32 to drive the gate elements 30 to their open positions only when the level of the logs 12 in the receiver 24 is below a predetermined level and a log 12 is transported by the conveyor 14 directly above the receiver 2 6. This is accomplished by the employment of a level sensing or detecting means for sensing when the level of logs 12 in the receiver 24 attains a predetermined level, the use of actuating means for energizing the valve solenoids when a log 12 is directly above the receiver 245, and the interconnec tion of the level sensing and actuating means such that the level sensing means prevents the actuating means from energizing the valve solenoids when the predetermined level of logs l2 in the receiver 2 is attained.

More particularly, the level sensing means comprises an electrical light source 48 arranged to direct a light beam $43 at a predetermined level across the receiver 24 and onto a light receiver 52. The light receiver $2 is connected by an electrical lead 54 to the electrical control system, indicated schematically as 56 in FIG. l and shown in more detail in H6. 4-, to prevent energization of the valve solenoids when the light beam 50 is blocked by logs 12 from the light receiver 52. The actuating means comprises an electrical light source 5% arranged to direct a light beam 60 across the conveyor l and onto a light receiver 62 at a location adjacent the juncture of the gate elements 30 in their closed positions. The light source 58 and light receiver 62 are positioned at a height whereby a log 12 transported by the conveyor 14 at their location blocks the light beam 60 from the light receiver 62; and the latter is electrically connected to cause energization of the valve solenoids at the time of such light blockage. The electrical control system 56, as schematically illustrated in FIG. 1, is electrically connected to the valve solenoids by an electrical lead 66.

Referring more particularly to the pneumatic and electrical control systems of the apparatus 10, these systems are shown in FIG. 4 in their normal condition with the electrical power shut off. As illustrated in FIG. 4, the electrical control system is powered by an electrical power source 68 and includes electrical inputs 70,72 and switches 74,76 which are controlled by the light receivers 52,62, respectively, and arranged in series in a circuit across the inputs 70,72. The switch 74 controlled by the light receiver 52 is normally open with the power source 68 shut off and is also opened when the light beam 56 is blocked by logs 12 from the light receiver 52; however, the light receiver 52 is responsive to the light beam 59 to maintain this switch 74 closed when the level of logs 12 in the receiver 24 does not block the light beam 50. The switch 76 controlled by the light receiver 62 is normally closed with the power source 68 shut off and is also closed whenever a log 12 on the conveyor 14 blocks the light beam 6% from the receiver 62, but is maintained open when the light beam 60 is received by the light receiver 62. Thus, as will be seen, electrical power is transmitted through the switches 74,76 only when the log level in the receiver 24 is below the predetermined level and a log 12 on the conveyor 14 blocks the light beam 66 from the light receiver 62.

The pneumatic control system comprises a pair of identical, spool-type valves 78 each controlling the flow of pressurized air to one of the cylinder-and-piston arrangements 32. The valves 78 are each biased by a spring 80 to a position wherein, as illustrated in FIGS. 1 and 8, the pressurized air causes extension of the pistons from the cylinders 38. Hence, as will be seen, this arrangement causes the gate elements 30 to be normally maintained in their illustrated closed positions. The valves 78 are shifted to positions wherein pressurized air is supplied to the cylinders 38 to cause retraction of the pistons into the cylinders 38 and resultant opening of the gate elements 30, by energization of normally deenergized solenoids 82,84 which are interposed in the electrical circuit containing the switches 7 3,76 and arranged to be energized substantially immediately upon the closing of both switches 74,76. The valves 78 each are particularly constructed such that, during their movement to these latter positions, prior to supplying pressurized air to one end of the cylinders 3b to move the pistons to their retracted positions the other end of the cylinders 38 areconnected to exhaust. A timer 86 is interposed in the electrical circuit containing the switches 74,76 to be actuated by the closing of both of the switches. The timer 86 is electrically connected to a normally open switch 238, interposed in a shunt 90 bypassing the switches 74,76, to close the switch S5 for an adjustable predetermined time period upon its actuation. Thus, assuming both of the switches 74,76 to have been closed, electrical current continues to be supplied to the solenoids 82,84 for an adjustable time period after the log 12 on the conveyor 14 starts to fall into the receiver 24 and the switch 76 is resultantly opened by the light receiver 62.

In the operation of the apparatus Ill, electrical power from the source 68 is normally continuously transmitted through the inputs 70,72 to the aforedescribed electrical circuit. The switch 74, assuming the logs 12 in the receiver 24 to be below the level of the light beam 50, is closed; and the switch 76, assuming no log 12 to be blocking the light beam 60, is conversely open. As a result, the springs normally retain the valves 78 in positions in which the pistons are extended and the gate elements 36 are resultantly closed. When, however, a log 12 transported by the conveyor 14 blocks the light beam 60 from the light receiver 62, the latter closes the switch 76 to thereby cause energization of the solenoids 82,84. The solenoids 82,84, thus energized, shift the valves 78 to positions in which pressurized air is supplied to' the cylinders 38 to retract the pistons and move the gate elements 30 longitudinally along the conveyor 14 to open positions. The log 12 interrupting the light beam 60 resultantly falls from the conveyor 14 into the receiver 24. The solenoids 82,84 are not immediately deenergized upon the movement of such log 12 out of the light beam 60, however, as the timer 86 maintains the switch 88 closed to permit electrical current to flow through the shunt 90 an ad justable additional period of time after the switch 76 opens. Upon the expiration of this additional time period, the solenoids 82,84 are deenergiaed whereby the springs 80 return the valves 78 and the gate elements 30 are resultantly reclosed.

When, however, logs 12 in the receiver 24 block the light beam 50 from the light receiver 52, the latter maintains the switch 74 open. Thus, the closing of the switch 76 by the light receiver 62 is ineffective to energize the solenoids 82,84; and the logs 12 transported by the conveyor 14 continue across the gate elements 30 and past the receiver 24 to another point of discharge which may be, for example, another receiver connected in series with the illustrated receiver 24. The conveyor 14 continues to transport the logs 12 past the receiver 24 until the level of logs 12 in the latter falls sufiiciently to permit the light beam 50 to be received by the light receiver 52 whereupon the logs 12 are again supplied to the receiver 24 in the aforedescribed manner.

From the preceding description, it will be seen that the construction of the conveyor M is particularly suited to cause the driving elements 38 to be the sole driving engagement between the conveyor 14 and the logs l2. Thus, the inclined or angled construction of these elements 18 facilitates the discharge of logs 12 from the conveyor 14. Moreover, the rapid movement of the gate elements 30 longitudinally along the conveyor prevents logs 12 from hanging-up thereon during the open ng of the latter and facilitates rapid opening of the gate to an open position in which the log fall space is sufficiently great to permit log discharge. In addition, the construction and arrangement of the pneumatic and electrical control systems are particularly suited to insure extremely rapid opening of the gate elements 30 and resultant highly efiicient operation of the apparatus.

FIG. 5 and 6, wherein components similar to those of the apparatus 10 are designated by the reference character for their aforedescribed similar component followed by the sufiix a, illustrates a material handling apparatus 10a which is constructed in accordance with an alternative embodiment of the invention. The apparatus 10a, as will become apparent from the following description, is particularly adapted for removing overlength logs from a conveyed stock of logs 12a. The conveyor 14a is identical in construction to the before-described conveyor 14 and is longitudinally driven in the direction of the arrow A shown to the left-hand side of FIG. 5. The conveyor Ma transversely receives logs from a log feed system shown as including an inclined log feed chute 92 which discharges to the conveyor Me at its lower end and at its upper end is arranged to receive logs 120 from a conventional feed conveyor illustrated fragmentarily as 9 A log-aligning plate 26 is positioned on the opposing side of the conveyor Ma from the feed chute 2 and angled to the conveyor 14a. The aligning plate 96 serves, during the operation of the apparatus lda, to align the forward or lead end of the logs 12a supplied to the conveyor 14a by the feed chute Q2.

The gate of the apparatus llla comprises only a single gate element 93 which is positioned below the support 20a for controlling the discharge of logs 12a from the conveyor 14a to the receiver 24a. The gate element 98 is particularly constructed of greater width than the maximum length of the logs 12a transported by the conveyor Ma and is normally maintained in its illustrated closed position wherein it prevents log discharge to the receiver 24a. The gate element 9% is slidably mounted for movement longitudinally along the conveyor 14a between its illustrated closed position and an open position permitting log discharge to the receiver 240; and, although shown as opening by movement in the direction counter to the direction in which the logs 12a are transported by the conveyor Ma, could be alternatively arranged to open by movement in such latter direction. The gate element 98 is driven longitudinally along the conveyor Ma by a double-acting, cylinder-andpiston arrangement which is designated generally as 312a and identical to the aforedescribed arrangements 32. The cylinder'and-piston arrangement 32a is connected to the pneumatic control system 100 of the apparatus a by airhoses 132a, 232a; and the pneumatic control system 160 is connected to a conventional source of pressurized air by a pneumatic supply hose 102. The pneumatic control system 1% includes a valve of the type shown as 78 in FIG. 4 and operable upon energization of a normally deenergized solenoid to supply pressurized air to the cylinder 38a through the airhose 232a.

A sensing means is provided for detecting the presence on the conveyor 14a of logs 12a of a predetermined length and for causing the gate element his to open whenever such an oversized log 12a is thereabove. More particularly, this sensing means comprises an electrical light source 104 arranged to vertically direct a light beam onto a vertically aligned light receiver 1%. The light source 104 and light receiver 106 are arranged adjacent the side of the conveyor 14c opposite to the aligning plate 96 and are spaced from the conveyor lla a distance commensurate with the predetermined length of overlength log 12a to be detected. Thus, although logs 12a of a length less than the predetermined length will not block the light beam emitted by the light source 1% from the receiver 1%, logs 12a of such predetermined length will so block the light beam. The light source l and receiver 106 are connected to the electrical control system N2 of the apparatus ltla by electrical leads 3%,110, respectively, whereby the blockage of the light beam from the receiver 106 closes a switch to cause the electrical control system 112 to energize the valve solenoid of the control system 100 through an electrical lead 11M. This switch is, as will be understood, normally open when the light beam is received by the receiver 1%; and the valve solenoid is resultantly normally deenergized.

in the operation of the apparatus Illa, the gate element 98 is normally maintained in its illustrated closed position. When, however, a log l2a of the aforementioned predetermined length passes-above the gate element 98, the light beam emitted by the light source 104 is blocked from the receiver res. Thus, the solenoid operating the valve of the pneumatic control system 1630 is then energized to cause pressurized air to be supplied to the cylinder 32a through the air conduit 232a to rapidly openthe gate element 93.

From the preceding description it will be seen that l have provided new and improved means for accomplishing all of the objects and advantages of my invention. it will be understood, however, that the gate illustrated in the embodiment of my invention shown in FIGS. 1 through 4 could be substituted for that of the embodiment of FIGS. 5 and 6; and, moreover, the gate of FIGS. 5 and 6 could be conversely substituted in the embodiment shown in F168. 1 through 3.

Moreover, although I have illustrated and hereinbefore specifically described only two embodiments of my invention, it will be understood that these embodiments have been given by way of illustration only and that my invention is not limited merely to these embodiments, but rather extends to all embodiments and variations within the scope of the following claims.

l claim:

1. A material handling apparatus comprising a conveyor longitudinally driven to transport material along a predeter mined path, a receiver below said conveyor and arranged to receive material from said conveyor, a gate comprising at least one gate element normally preventing discharge of material from said conveyor to said receiver and movable longitudinally to said conveyor to permit such discharge, fluid operated cylinder-and-piston means connected to said gate element and actuatable for moving said gate element to permit said discharge, and actuating means responsive to the size of material transported by said conveyor for actuating said cylinder-andpiston means.

2. The apparatus of claim 1, wherein said actuating means is responsive to the length of material transported by said conveyor for actuating said cylinder-and-piston means.

3. The apparatus of claim 1, wherein said conveyor includes a plurality of driving elements angled in the direction of the movement of said conveyor.

4. The apparatus of claim 1, wherein means control said cylinder-and-piston means whereby, prior to the supply of pressurized fluid to oneend of the cylinder for moving said gate element to permit said discharge, the other end of said cylinder is connected to exhaust.

5. A material handling apparatus comprising a conveyor longitudinally driven to transport material along a predetermined path, a receiver below said conveyor and arranged to receive material from said conveyor, a gate comprising a pair of gate elements normally in closed positions preventing discharge of material from said conveyor to said receiver andmovable one from the other in directions longitudinally along said conveyor to open positions permitting such discharge, fluid operated cylinder-and-piston means connected to each of said gate elements actuatable for moving said gate elements to said open positions, actuating means responsive to the material transported by said conveyor above said receiver for actuating said cylinder-and-piston means, and sensing means responsive to the level of material in said receiver operable, when material in said receiver attains a predetermined level, for preventing actuation of said cylinder-and-piston means.

6. The apparatus of claim 5, wherein said conveyor includes driving elements extending thereacross, and said driving elements are angled in the direction of the movement of the conveyor and arranged to be the sole driving engagement between said conveyor and material transported thereby.

7. The apparatus of claim 5, wherein means control each of said cylinder-and-piston means whereby, prior to the supply of pressurized fluid to one end of the cylinder thereof for moving said gate elements to said open positions, the other end of such cylinder is connected to exhaust.

d. The apparatus of claim 5, wherein said actuating means includes means arranged to detect the presence of material at a location adjacent the adjacent ends of said gate elements.

9. A material handling apparatus comprising a conveyor longitudinally driven to transport material along a predetermined path, a receiver arranged to receive material from said conveyor, a gate comprising at least one gate element normally preventing discharge of material from said conveyor to said receiver and movable in a direction longitudinally to said conveyor to permit such discharge, driving means connected to said gate element actuatable for moving said gate element to permit such discharge, actuating means responsive to the material transported by said conveyor adjacent said receiver for actuating said driving means, and means responsive to the level of material in said receiver operable, when materialin said receiver attains a predetermined level, for preventing actuation of said driving means, said conveyor including a pair of longitudinally driven, laterally spaced, endless elements and driving elements extending transversely between the endless elements at locations spaced along the length of the conveyor, and said driving elements being connected to said endless elements and being angled in the direction of the movement of the conveyor.

10. The apparatus of claim 9, wherein said driving means comprises cylinder-and-piston means and means control the 

1. A material handling apparatus comprising a conveyor longitudinally driven to transport material along a predetermined path, a receiver below said conveyor and arranged to receive material from said conveyor, a gate comprising at least one gate element normally preventing discharge of material from said conveyor to said receiver and movable longitudinally to said conveyor to permit such discharge, fluid operated cylinder-andpiston means connected to said gate element and actuatable for moving said gate element to permit said discharge, and actuating means responsive to the size of material transported by said conveyor for actuating said cylinder-and-piston means.
 2. The apparatus of claim 1, wherein said actuating means is responsive to the length of material transported by said conveyor for actuating said cylinder-and-piston means.
 3. The apparatus of claim 1, wherein said conveyor includes a plurality of driving elements angled in the direction of the movement of said conveyor.
 4. The apparatus of claim 1, wherein means control said cylinder-and-piston means whereby, prior to the supply of pressurized fluid to one end of the cylinder for movinG said gate element to permit said discharge, the other end of said cylinder is connected to exhaust.
 5. A material handling apparatus comprising a conveyor longitudinally driven to transport material along a predetermined path, a receiver below said conveyor and arranged to receive material from said conveyor, a gate comprising a pair of gate elements normally in closed positions preventing discharge of material from said conveyor to said receiver and movable one from the other in directions longitudinally along said conveyor to open positions permitting such discharge, fluid operated cylinder-and-piston means connected to each of said gate elements actuatable for moving said gate elements to said open positions, actuating means responsive to the material transported by said conveyor above said receiver for actuating said cylinder-and-piston means, and sensing means responsive to the level of material in said receiver operable, when material in said receiver attains a predetermined level, for preventing actuation of said cylinder-and-piston means.
 6. The apparatus of claim 5, wherein said conveyor includes driving elements extending thereacross, and said driving elements are angled in the direction of the movement of the conveyor and arranged to be the sole driving engagement between said conveyor and material transported thereby.
 7. The apparatus of claim 5, wherein means control each of said cylinder-and-piston means whereby, prior to the supply of pressurized fluid to one end of the cylinder thereof for moving said gate elements to said open positions, the other end of such cylinder is connected to exhaust.
 8. The apparatus of claim 5, wherein said actuating means includes means arranged to detect the presence of material at a location adjacent the adjacent ends of said gate elements.
 9. A material handling apparatus comprising a conveyor longitudinally driven to transport material along a predetermined path, a receiver arranged to receive material from said conveyor, a gate comprising at least one gate element normally preventing discharge of material from said conveyor to said receiver and movable in a direction longitudinally to said conveyor to permit such discharge, driving means connected to said gate element actuatable for moving said gate element to permit such discharge, actuating means responsive to the material transported by said conveyor adjacent said receiver for actuating said driving means, and means responsive to the level of material in said receiver operable, when material in said receiver attains a predetermined level, for preventing actuation of said driving means, said conveyor including a pair of longitudinally driven, laterally spaced, endless elements and driving elements extending transversely between the endless elements at locations spaced along the length of the conveyor, and said driving elements being connected to said endless elements and being angled in the direction of the movement of the conveyor.
 10. The apparatus of claim 9, wherein said driving means comprises cylinder-and-piston means and means control the cylinder-and-piston means such that, prior to the supply of pressurized fluid to one end of the cylinder thereof for moving the gate element to permit the discharge, the other end of such cylinder is connected to exhaust. 